This paper studies whether opposite opinions about an important yet payoff-irrelevant topic deteriorate trust and trustworthiness and offset the well-documented positive effect of communication. In an experimental setting, we vary the importance of the topic and the participants’ ability to communicate. When the topic is polarizing enough, communication no longer improves trust and even harms trustworthiness. Using unsupervised machine learning, we document that a substantial fraction of individuals focus their communication on being polarized leading to significant deterioration of both trust and trustworthiness.